“It’s worth noting how much easier it is to successfully solve ReCAPTCHAs when the user is logged into their Google account”. Well to me it makes absolute sense as Google knows that the logged in user is a human. This article is just following the current trend all Google is bad.
Right, someone can't register a google account and make their spambots bypass CAPTCHAs with it. Just knowing that a human was present once doesn't mean they are always human. Googlen probably lets you pass easily once or twice in a certain amount of time but keeps track and starts giving you more difficult solves as time goes on. But then, someone might register a thousand google accounts and rotate through them to allow cool off time, so I'm not sure how this is handled. It is not a given that rewarding people with a google account is a good thing.
However, when the california DMV website will log you into google just by browsing and integrates recaptcha to do online transactions such as making an appointment, it gets real.